But i've seen a few (mainly just 2... th iphone and t-mobile's rocker) other phones have an app where they can just hold up there phone towards the closest speaker or just in mid air .. and it identifies the song playing for you, with the title, artist and album.

as a music LOVER .. i def. can find great use for this app. and will highly consider paying for this.

Can anyone come up with it?? or more importantly.. does it already exist??

Yeah, Shazam is the company that has made a big splash doing this for the iPhone (and Android and Blackberry). But as pointed out, Palm doesn't currently provide access to the microphone for programmers, so it could be a while for the Pre.

Use Pandora or AccuRadio instead of the radio and they tell you what they're playing (just kidding ... sort of) 8^).